Blasting is a common technique in mining for fracturing a substrate, such as rock, to facilitate excavation and removal. Blasting involves controlled explosions, typically using shells that contain an explosive charge that is initiated by a detonator. A detonator is a device for initiating an explosive, and may be in the form of an explosive device that has transmission wires/leads attached to initiate the explosive from a remote position on the surface. The explosive charge is primed with the detonator sitting in the explosive or explosive cavity region, with the transmission wires/leads protruding outside the shell and any attached anchoring devices up to the surface of the blasthole.
There exists a problem in that the reliability of operation of the shell may be detrimentally impacted where a detonator is not positioned up against an end of a cavity within a booster shell. This positioning increases the chance of a misfire and potentially reduces booster output. Accordingly, it would be advantageous to provide a shell design which allows detonators having different lengths to be securely enclosed and positioned in a correct location inside the booster shell.
In embodiments, the present invention seeks to provide a shell which overcomes or at least alleviates one or more disadvantages associated with existing shells.